Question

Find the magnitude and direction angle of r=-48i+6j.

I think I understand how to get the magnitude but not understanding the direction angle...

Answer 1

So to get the magnitude would be
\[\sqrt{-48^{2}+6^{2}}\]

Answer 2

I think.

Answer 3

you are right on the magnitude

Answer 4

So the direction angle goes back to a unit circle?

Answer 5

Or am I just crazy

Answer 6

yeah it pretty much does, all the unit circle is is a way to look at angles, so take
tan(x) = opp/ adj
tan(x) = 6/48 <-- 48 is positive because it's just a magnitude
the angle in the triangle is atan(6/48)

Answer 7

so the direction from positive x is 180 - that angle found

Answer 8

Okay then would the magnitude be kept in a fraction form 'cause the decimal goes on forever o.o

Answer 9

the magnitude is up to you or however your teacher wants it. it is safe to round off usually to 2 decimals

Answer 10

:) okay awesome that makes sense! Thanks a lot.

Answer 11

no problem, glad to help